TY - CONF AU - Tang, Y AU - Lombardi, Michael AU - Howe, David C2 - 2004 IEEE Conf. Precision Electromagnetic Measurements , London, 1, UK DA - 2004-01-01 00:01:00 LA - en PB - 2004 IEEE Conf. Precision Electromagnetic Measurements , London, 1, UK PY - 2004 TI - Frequency Uncertainty Analysis for Josephson Voltage Standard ER -